Will u come to China in early Oct? If so, the weather of most places are mild. Beijing and Xian will be sunny and dry, Shanghai, Hangzhou and Putuoshan is also sunny but a little humid. There may be rainfall in Guilin but not cold.
Ps: the temperature varies greatly in the morning and night.

If you come here at the end of Oct, the weather will be somewhat cool. Anyway, you'd better pay attention to the weather forecast.